Multi-mode power amplifier module

ABSTRACT

A power amplifier that can support multiple communication networks while maintaining power efficiency across each of the supported communication networks is disclosed. In some implementations described herein, a power amplifier module includes a bypass circuit that enables different voltage supplies to be provided to the power amplifier. By regulating the voltage supply provided to the power amplifier, the power amplifier can support different communication networks while maintaining power efficiency across a dynamic frequency range. Moreover, embodiments herein may include a buck converter, or other form of DC-DC converter, that enables the power amplifier to operate with respect to multiple communication networks. Advantageously, in certain embodiments, because wireless devices that include multiple power amplifiers often require a DC-DC converter to support at least some of the communication networks, the inclusion of the buck converter in the embodiments described herein does not add additional cost or size to the wireless device.

RELATED APPLICATIONS

This disclosure claims priority to U.S. Provisional Application No.62/272,963, which was filed on Dec. 30, 2015 and is titled “MULTI-MODEPOWER AMPLIFIER MODULE,” the disclosure of which is expresslyincorporated by reference herein in its entirety for all purposes. Anyand all applications, if any, for which a foreign or domestic priorityclaim is identified in the Application Data Sheet of the presentapplication are hereby incorporated by reference in their entiretiesunder 37 CFR 1.57.

BACKGROUND

Technical Field

This disclosure relates to a power amplifier module. More specifically,this disclosure relates to a multi-mode power amplifier module.

Description of Related Technology

Wireless devices, such as cellphones, typically use one or more poweramplifiers to amplify an information signal prior to transmission.Often, a wireless device will include a plurality of power amplifiers tosupport a plurality of communication modes. There is a tension betweensupporting more communication modes and services, and reducing the costand size of the wireless device. The more communication modes supported,the more space required by the wireless device to support thecommunication components, including the power amplifier.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the drawings, reference numbers are re-used to indicatecorrespondence between referenced elements. The drawings are provided toillustrate embodiments of the inventive subject matter described hereinand not to limit the scope thereof.

FIG. 1 illustrates a block diagram of an embodiment of a front-endmodule.

FIG. 2 illustrates a circuit diagram of an embodiment of the front-endmodule of FIG. 1.

FIGS. 3A and 3B illustrate a circuit diagram of an embodiment of abypass switch included in a power amplifier module.

FIG. 4 illustrates a more detailed circuit diagram of an embodiment ofthe bypass switch of FIGS. 3A and 3B.

FIG. 5 illustrates a graph of the measured power and current for a 2Gpower amplifier with a reduced supply voltage.

FIG. 6 presents a flowchart of an embodiment of a power amplifierconfiguration process.

FIG. 7 illustrates a block diagram of an embodiment of a wirelessdevice.

SUMMARY

The systems, methods and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for theall of the desirable attributes disclosed herein. Details of one or moreimplementations of the subject matter described in this specificationare set forth in the accompanying drawings and the description below.

Certain aspects of the present disclosure relate to a power amplifiermodule. The power amplifier module may include a first power amplifierconfigured to process frequencies associated with a first communicationband and a bypass switch in communication with the first poweramplifier. The bypass switch may be configured to provide a supplyvoltage to the first power amplifier. This supply voltage may beselected from a plurality of supply voltages based at least in part on aselected communication network. At least one of the supply voltages fromthe plurality of supply voltages may enable the first power amplifier toprocess frequencies associated with a second communication.

In certain embodiments, the plurality of supply voltages includes abattery supply voltage and a buck-converter supply voltage. Further, thebypass switch may include a p-channel field effect transistor incommunication with a battery supply voltage. In addition, the bypassswitch may include a p-channel field effect transistor and an n-channelfield effect transistor in communication with a buck-converter supplyvoltage.

Some implementations of the power amplifier module may further include asecond power amplifier in communication with a battery supply voltagewithout being in communication with the bypass switch. The second poweramplifier may be configured to process frequencies associated with 2Gcommunication of a different frequency band than the frequenciesprocessed by the first power amplifier. In some cases, the firstcommunication band is a 2G communication band and the secondcommunication band is a non-2G communication band.

Certain aspects of the present disclosure relate to a front-end module.The front-end module may include a power amplifier module that includesa first power amplifier and a bypass switch in communication with thefirst power amplifier. The first power amplifier may be configured toprocess a frequency associated with a first communication band. Thebypass switch may be configured to provide a supply voltage to the firstpower amplifier. The supply voltage may be selected from a plurality ofsupply voltages based at least in part on a selected communicationnetwork. At least one of the supply voltages from the plurality ofsupply voltages may enable the power amplifier to process a frequencyassociated with a second communication band. Further, the front-endmodule may include a direct current-direct current converter incommunication with the power amplifier module. The direct current-directcurrent converter may be configured to provide at least one supplyvoltage from the plurality of supply voltages to the bypass switch.

In certain embodiments, the direct current-direct current converterincludes a buck converter. Moreover, the front-end module may furtherinclude an inductor-capacitor circuit between the direct current-directcurrent converter and the bypass switch. In some cases, the plurality ofsupply voltages includes a battery supply voltage and a buck-convertersupply voltage. Further, the bypass switch may include a p-channel fieldeffect transistor in communication with a battery supply voltage. Insome cases, the bypass switch may include a p-channel field effecttransistor and an n-channel field effect transistor in communicationwith a buck-converter supply voltage.

With some implementations of the front-end module, the power amplifiermodule further includes a second power amplifier in direct communicationwith a battery supply voltage. Further, the second power amplifier maybe configured to process a different frequency associated with 2Gcommunication than the frequency processed by the first power amplifier.

Certain aspects of the present disclosure relate to a wireless device.The wireless device may include an antenna and a front-end module. Theantenna may be configured to transmit a signal from the front-endmodule. The front-end module may include a power amplifier module and adirect current-direct current converter in communication with the poweramplifier module. The power amplifier module may include a first poweramplifier and a bypass switch in communication with the first poweramplifier via a first communication path. The power amplifier may beconfigured to process a frequency associated with a first communicationnetwork. Further, the bypass switch may be configured to provide asupply voltage to the first power amplifier. The supply voltage may beselected from a plurality of supply voltages based at least in part on aselected communication network from a plurality of communicationnetworks. At least one of the supply voltages from the plurality ofsupply voltages may enable the first power amplifier to process afrequency associated with a second communication network. The directcurrent-direct current converter may be configured to provide at leastone supply voltage from the plurality of supply voltages to the bypassswitch.

In certain embodiments, the bypass switch includes a single transistorin communication with a battery supply voltage. In some implementations,the bypass switch includes a pair of transistors in communication with adirect current-direct current converter supply voltage. In some cases, afirst transistor of the pair of transistors is a p-channel transistorand the second transistor of the pair of transistors is an n-channeltransistor. Further, the power amplifier module may further include asecond power amplifier in communication with a battery supply voltagevia a second communication path. The second power amplifier may beconfigured to process a different frequency associated with the firstcommunication network than the frequency processed by the first poweramplifier.

DETAILED DESCRIPTION

Introduction

It is typically desirable to design wireless or mobile devices tosupport multiple communication standards, networks or technologies. Forexample, wireless devices may be designed to support 2G, 2.5G, 3G, 4G,4G LTE, 5G, WiMAX, GSM, CDMA, etc. One reason for supporting multiplecommunication networks is to enable the wireless device to be used indifferent geographic locations or with different service providers.However, in order to support multiple communication networks, it isoften necessary for the wireless device to include multiple poweramplifiers. In some implementations, a separate power amplifier may beincluded for each supported communication network, and in some casesmultiple power amplifiers may be included for a supported communicationnetwork. For example, some devices may include two or three poweramplifiers to support 2G communication, another power amplifier tosupport 3G communication, and an additional power amplifier to support4G and/or 4G LTE communication. The inclusion of multiple poweramplifiers results in larger, more complex, and more expensive devices.

One solution is to include a power amplifier in the wireless device thatis capable of supporting multiple communication networks. However,different communication networks require the power amplifier to supportdifferent power ranges. Thus, the voltage supply provided to the poweramplifier should be high enough to support each of the communicationnetworks supported by the wireless device. For example, for wirelessdevices that support 2G, 3G, and 4G communication, the power amplifierreceives a voltage equivalent to the battery supply of the wirelessdevice because, typically, 2G communication requires a higher powerlevel than 3G and 4G communication. Consequently, the power efficiencyof the power amplifier is reduced compared to devices that includeseparate power amplifiers when supporting 3G and 4G communication, whichtypically require lower power than 2G communication.

In certain embodiments described herein, a power amplifier that cansupport multiple communication networks while maintaining powerefficiency across each of the supported communication networks isdisclosed. In some implementations described herein, a power amplifiermodule includes a bypass circuit that enables different voltage suppliesto be provided to the power amplifier. By regulating the voltage supplyprovided to the power amplifier, the power amplifier can supportdifferent communication networks while maintaining power efficiencyacross a dynamic frequency range. Moreover, embodiments herein mayinclude a buck converter, or other form of DC-DC converter, that enablesthe power amplifier to operate with respect to multiple communicationnetworks. Advantageously, in certain embodiments, because wirelessdevices that include multiple power amplifiers often require a DC-DCconverter to support at least some of the communication networks, theinclusion of the buck converter in the embodiments described herein doesnot add additional cost or size to the wireless device. Further, someembodiments disclosed herein support time-division long term evolution(TD-LTE) while reducing the size and power requirements of the wirelessdevice compared to systems that do not include multi-mode poweramplifiers. Moreover, some embodiments disclosed herein can supporttime-division-code division multiple access (TD-CDMA).

Example Front-End Module

FIG. 1 illustrates a block diagram 100 of an embodiment of a front-endmodule (FEM) 102. The FEM 102 may be part of a transmission path that isin communication with an antenna that can transmit a signal to adestination, such as a base station. The FEM 102 may include a poweramplifier module 104 and a buck converter 110. Although a single poweramplifier module 104 is illustrated, in some cases, the FEM 102 mayinclude multiple power amplifier modules.

The buck converter 110 can modify a voltage received from a powersupply, such as a battery. For example, the buck converter 110 can stepdown the voltage received from the power supply. In some cases, the buckconverter 110 may be combined with a buck boost, which can be used tostep up the voltage received from the power supply. Moreover, althoughillustrated as a buck converter, FEM 102 may include other types ofDC-DC converters instead of or in addition to the buck converter 110.

The power amplifier module 104 may include one or more power amplifiers108 and a bypass switch 106. As used herein, power amplifiers 108 mayrefer to a single power amplifier or a plurality of power amplifiers. Insome cases, each of the plurality of power amplifiers may be associatedwith a single communication network or technology. For example, theplurality of power amplifiers may each support different communicationbands of a 2G communication network. In some cases, the one or morepower amplifiers 108 may include a power amplifier that can supportmultiple communication networks. The bypass switch 106 enables theselection of different voltage supplies to be provided to the poweramplifiers 108 based on the selected communication network. For example,for a 2G communication network, the bypass switch 106 may provide abattery supply to the power amplifiers 108. However, for a 3Gcommunication network, the bypass switch 106 may provide a voltagesupply received from the buck converter 110 to the power amplifiers 108.Although referred to as a switch herein, the bypass switch 106 may alsobe referred to as a bypass circuit and may include one or more switches.

Example Circuit Diagram of a FEM

FIG. 2 illustrates a circuit diagram 200 of an embodiment of thefront-end module 102 of FIG. 1. As illustrated in FIG. 2, the poweramplifiers 108 may include multiple power amplifiers 204, 206. However,in some embodiments, the power amplifier module 104 may include more orless power amplifiers. For example, the power amplifier module 104 mayinclude a high band power amplifier in addition to the low band (LB) PA204 and the mid band (MB) PA 206. Further, the power amplifiers 204 and206 are illustrated as three stage power amplifiers. However, the poweramplifiers 204 and 206 are not limited as such and may have more orfewer stages.

In the illustrated embodiment, the power amplifier 204 is a 2G low bandpower amplifier and receives a voltage supply from a Vbat input to theFEM 102. Further, as illustrated, the power amplifier 204 receives thevoltage supply directly from the Vbat input. Although termed Vbat, itshould be understood that, in certain embodiments, the voltage suppliedmay be received from a power source other than a battery, such asanother regulator or DC-DC converter. Further, although the low bandpower amplifier 204 is described as a 2G low band power amplifier, itshould be understood that the power amplifier may support non-2Gcommunication bands. For example, the power amplifier 204 may supportlow band 4G communication.

The power amplifier 206 represents the power amplifier that is capableof supporting multiple communication networks. In other words, in somecases, the 2G mid band power amplifier 206 may be reused to supportadditional communication networks. For example, the power amplifier 206may support a 2G mid-band or 2G high band communication network.Moreover, the power amplifier 206 may support non-2G communicationnetworks, such as a 3G, 4G, or 4G LTE communication network. The poweramplifier 206 receives its voltage supply via the bypass switch 106,which can control whether the power amplifier 206 receives a voltagesupply from the Vbat input or from a DC-DC converter, such as the buckconverter 110.

In some embodiments, the buck converter 110 may be in communication withthe bypass switch 106 via an LC circuit 202. Advantageously, in certainembodiments, by using the bypass switch 106 to regulate whether thepower amplifier 206 receives power from the buck converter 110 ordirectly from the Vbat, the size of the LC circuit 202 may be reducedcompared to other power amplifier module designs that include a largebuck converter without a bypass switch. Further, in certain embodiments,the use of the bypass switch 106 enables the size of the DC-DC converter(e.g., the buck converter 110) that is used to support the non-2Gcommunication networks (e.g., 3G or 4G communication networks) to bereduced compared to systems that do not include the internal bypassswitch 106 in the power amplifier module 104. Moreover, in some cases,the power amplifier module 104 is more power efficient compared tosystems that do not include the bypass switch 106 to control the voltagesupplied to the PA 206.

In FIG. 2, only the power amplifier 206 is connected to the bypassswitch 106. The low band PA 204 is not connected to the bypass switch106 because generally the power required for the low band PA 204 is ator near that supplied by the battery. Further, connecting the low bandPA 204 to a power supply via the bypass switch 106 would require anincrease in the size of the bypass switch 106. However, in certainembodiments, the bypass switch 106 can be configured to support the lowband PA 204. In such cases, the low band PA 204 can be connected to apower supply via the bypass switch 106. Further, the bypass switch 106may be expanded to support the connection to both the PAs 204 and 206.

Advantageously, in certain embodiments, by supporting the application ofdifferent power supply voltages to the power amplifier 204 or 206, thefront-end module 102 can support multiple communication bands withoutrequiring the inclusion of a power amplifier for each communicationband. Further, the front-end module 102 can support multiplecommunication bands while optimizing the amount of power required by thepower amplifier to support each communication band.

Example Bypass Switch Circuit

FIG. 3A illustrates a circuit diagram of an embodiment of a bypassswitch 106 included in a power amplifier module 104. As illustrated inFIG. 3A, the bypass switch 106 may be a switch circuit that includes anumber of circuit elements, including one or more switches. The bypassswitch 106 may include an inverter 302 and a pair of switches 304 and306. The inverter 302 may be used to control the switches 304 and 306.In response to receiving a buck enable signal, the switch 304 may beopened and the switch 306 may be closed, as illustrated in FIG. 3A,resulting in the buck converter supply being provided to the poweramplifier via the PA supply pin or node. Alternatively, or in addition,the switch 304 may be connected to an open load. By providing the buckconverter supply to the power amplifier 108, the power amplifier canfunction or operate with respect to a non-2G communication network ormode, such as a 3G or 4G communication network.

On the other hand, in response to receiving a non-buck enable signal,the switch 304 may be closed and the switch 306 may be opened, asillustrated in FIG. 3B, resulting in the battery supply being providedto the power amplifier via the PA supply node. Alternatively, or inaddition, the switch 306 may be connected to an open load. By providingthe battery supply to the power amplifier, the power amplifier canfunction in a 2G communication mode. The buck enable signal can be alogic zero or a logic one signal to indicate the operational mode of thepower amplifier and, consequently, the voltage supply to be provided tothe power amplifier.

As previously described, in some embodiments, both the PA 204 and the PA206 may be in communication with the bypass switch 106. Thus, while theswitches 304 and 306 may regulate power to the PA 206, the bypass switch106 may include additional switches in a similar configuration to theswitches 304 and 306 that can regulate the power supplied to the PA 204.

FIG. 4 illustrates a more detailed circuit diagram of an embodiment ofthe bypass switch 106 of FIG. 3A. As illustrated in FIG. 4, the switches304 and 306 may be implemented using one or more transistors. In theillustrated example, the switch 304 is implemented using a p-channelfield-effect transistor (pFET) 402. This pFET 402 is connected betweenthe battery power supply and the voltage supply port to the PA. Further,the inverter 302 is connected to the gate of the pFET 402 and cancontrol whether the pFET 402 passes the battery supply voltage to thesupply port of the PA. The battery voltage may depend on theimplementation of the wireless device. However, it is often the casethat the battery voltage will vary between 3.5 and 4.5 volts.

The switch 306 may be implemented using a pair of transistors that areconnected in parallel between the buck converter supply and the voltagesupply port to the PA. The transistor 406 may be a pFET and thetransistor 404 may be an n-channel FET (nFET). Using the transistor pair404 and 406 enables the switch 306 to support a battery voltage fromapproximately 0.5 volts up to the battery voltage (e.g., between 3.5 and4.5 volts). The combination of the nFET transistor 404 and the pFETtransistor 406 enables the switch 306 to have a low impedance throughoutthe entire dynamic voltage range supported by the bypass switch 106.Further, similar to the switch 304, the inverter 302 is connected to thegate of the nFET 404 and, in conjunction with the buck enable signalthat is provided to the gate of the pFET 406, can control whether theswitch 306 passes the buck converter supply voltage to the supply portof the PA.

Simulation Result

FIG. 5 illustrates a graph 500 of the measured power and current for a2G power amplifier with a reduced supply voltage as represented by theline 502. The graph 500 is the result of a simulation that illustratesthe operation of a 2G power amplifier when it is used to supportoperation of 3G or 4G communication by using a buck converter with anassumed efficiency of 90%, which is a conservative efficiency as manyDC-DC converters can have higher efficiencies. The effective currentconsumption can be calculated for the power amplifier using equation 1.

$\begin{matrix}{I_{BATT} = \frac{I_{PA} \times V_{PA}}{V_{BATT} \times \varnothing}} & (1)\end{matrix}$

The efficiency of the DC-DC converter is represented by Ø, which aspreviously stated is assumed to be 90%. Further, the battery voltage,V_(BATT), is set to 3.8 volts in this example and the power amplifiervoltage, V_(PA), is set to 2.7 volts. Thus, the current draw of thebattery may be calculated as I_(BATT)=I_(PA)×0.77. Thus, we can see fromthis calculation that there is an overall improvement of systemefficiency of 23% by operating the power amplifier using the DC-DCconverter to reduce the voltage supplied to the power amplifier insteadof operating at the battery voltage when the power amplifier is beingused for 3G or 4G communication. Thus, in certain embodiments, the useof the bypass switch 106 to facilitate operation of a power amplifier108 with respect to multiple communication networks can result ifpotential power efficiency savings of up to 23%. Referring to the graph500, we can see from the line 502 that at 23.5 dBm, the current from thebattery is measured as 444 mA.

Example Power Amplifier Configuration Process

FIG. 6 presents a flowchart of an embodiment of a power amplifierconfiguration process 600. The process 600 can be implemented by anysystem that can configure a power amplifier based, at least in part, onthe communication network and/or frequency band or bands being used tocommunicate with another device, such as a base station. For example,the process 600 may be performed by a front-end module 102, a basebandprocessor, a call processor, a controller, a central processor, a poweramplifier module 104, or a bypass switch 106, to name a few. Althoughone or more systems may implement the process 600, in whole or in part,to simplify discussion, the process 600 will be described with respectto particular systems.

The process 600 begins at the block 602 where, for example, a basebandprocessor of a wireless device receives an identification of acommunication network for transmission of a signal. The communicationnetwork may be identified by a device, such as a base station, that isin communication with the wireless device. Further, the identificationof the communication network may indicate a communication standardand/or a communication frequency with which the wireless device is tocommunication with the base station, or other device.

At decision block 604, the baseband processor determines whether thecommunication network is associated with 2G communication. Thisdetermination may be made based at least in part on the identificationof the communication network at block 602. Further, the determination atthe decision block 604 may include determining the communication networkand/or frequency band with which the wireless device is to communicatewith the base station (e.g., a 3G or 4G LTE network, etc.).

If it is determined at the decision block 604 that the wireless deviceis to use one or more 2G communication bands, the baseband processorcauses a battery supply voltage to be supplied to the power amplifier108 at block 606. The block 606 can include configuring the bypassswitch 106 such that the power amplifier receives a voltage from thebattery supply instead of from the buck converter 110, or another DC-DCconverter included in the wireless device. In some embodiments, thebypass switch 106 may be configured to not provide a voltage to thepower amplifier. This may occur, for example, when the communicationnetwork is determined to be a low band 2G network. The low band 2Gnetwork may be, for example, band 5, which may encompass frequenciesbetween 824 and 915 MHz. In contrast, the mid band 2G network may band4, which may encompass frequencies between 1710 and 1910 MHz. In caseswhere the communication network is determined to be a low band 2Gnetwork, the power amplifier 204, which is connected to the batteryvoltage supply via a separate path from the bypass switch 106, may beused during transmission.

If it is determined at the decision block 604 that the wireless deviceis to use a non-2G communication network, such as a 4G LTE network, thebaseband processor causes a DC-DC converter supply voltage to beprovided to the power amplifier 108 at block 608. Although not limitedas such, a 3G or 4G network may be between 1880 and 2025 MHz. In someembodiments, the power amplifier 206 can support one or more bandsbetween band 33 and 46. The block 608 can include configuring the DC-DCconverter to provide a supply voltage of a particular voltage based atleast in part on the specific communication network and/or frequencyband that the wireless device is to use for communication. Further, theblock 608 can include configuring the bypass switch 106 such that thepower amplifier receives a voltage from the DC-DC converter instead offrom the battery supply.

Example Wireless Device

FIG. 7 illustrates a block diagram of an embodiment of a wireless device700. The wireless device 700 includes a multi-chip module (MCM) 702 witha front-end module 102. This FEM 102 may include some or all of theembodiments previously described with respect to the FEM 102. In somecases, the multi-chip module 702 may include multiple FEMs. Althoughillustrated separately, in some implementations, the MCM 702 may be partof the transceiver 710.

In the example illustrated in FIG. 7, the FEM 102 includes a DC-DCconverter 110, one or more power amplifiers 108, and a bias circuit 704.As previously described, the PAs 108 may be included as part of a poweramplifier module, which may include a bypass switch. The bias circuit704 may bias the operating range of the power amplifiers 108. In someembodiments, the bias circuit 702 is optional or omitted. As previouslydescribed, the DC-DC converter 110 may be a buck converter. However, insome embodiments, the DC-DC converter 110 may be a different type ofDC-DC converter, such as a switched capacitor converter.

In addition to the FEM 102, the MCM 702 may include a number ofadditional systems configured to facilitate operation of the one or morePAs included in the FEM 102. For example, the MCM 702 may include a PAcontroller 752 and an impedance matching network 754. The PA controller752 may be configured to adjust the configuration of one or more PAs108. Adjusting the configuration of the PAs 108 may include configuringa bypass switch included in the FEM 102 and/or included in a poweramplifier module of the FEM 102. The PA controller 752 may adjust theconfiguration of a PA 108 based at least in part on a control signalreceived from a base station. In some cases, the baseband subsystem 708includes the PA controller 752 and/or provides a control signal to thePA controller 752 for configuring the PA 108.

The impedance matching network 754 may be configured to match one ormore impedance values between one or more circuits in a load line. Forinstance, the impedance matching network 554 may be configured to matchan impedance between the antenna 722A and the FEM 102.

In some cases, the MCM 702 can receive RF signals from a transceiver 710that can be configured and operated in known manners to generate RFsignals to be amplified and transmitted, and to process receivedsignals. The transceiver 710 is shown to interact with a basebandsubsystem 708 that is configured to provide conversion between dataand/or voice signals suitable for a user and RF signals suitable for thetransceiver 710. In some cases, the transceiver 710 may include the MCM702 and/or the FEM 102.

Further, the transceiver 710 may be connected to a power managementcomponent 706 that is configured to manage power for the operation ofthe wireless device. Such power management can also control operationsof the baseband sub-system 708 and the MCM 702. It should also beunderstood that the power management component 706 may include a powersupply, such as a battery. Alternatively, or in addition, one or morebatteries may be separate components within the wireless device 700.

Other connections between the various components of the wireless device700 are possible, and are omitted from FIG. 7 for clarity ofillustration only and not to limit the disclosure. For example, thepower management component 706 may be electrically connected to thebaseband subsystem 708, the MCM 702, the DSP 712, or other components714. As a second example, the baseband subsystem 708 may be connected toa user interface processor 716 that may facilitate input and output ofvoice and/or data provided to and received from the user. The basebandsub-system 708 can also be connected to a memory 718 that may beconfigured to store data and/or instructions to facilitate the operationof the wireless device 700, and/or to provide storage of information forthe user.

In addition to the aforementioned components, the wireless device 700may include one or more central processors 720. Each central processor720 may include one or more processor cores. Further, the wirelessdevice 700 may include one or more antennas 722A, 722B. In some cases,one or more of the antennas of the wireless device 700 may be configuredto transmit and receive at different frequencies or within differentfrequency ranges. Further, one or more of the antennas may be configuredto work with different wireless networks. Thus, for example, the antenna722A may be configured to transmit and receive signals over a 2Gnetwork, and the antenna 722B may be configured to transmit and receivesignals over a 3G network. In some cases, the antennas 722A and 722B mayboth be configured to transmit and receive signals over, for example, a2.5G network, but at different frequencies. In some cases, the antenna722A may be a primary antenna and the antenna 722B may be a diversityantenna. Moreover, while both antennas 722A and 722B are illustrated asbeing on the same side of the wireless device 700, in some cases, theantennas 722A and 722B are on different sides or surfaces of thewireless device 700.

A number of other wireless device configurations can utilize one or morefeatures described herein. For example, a wireless device may or may notperform carrier aggregation. In another example, a wireless device caninclude additional antennas such as diversity antenna, and additionalconnectivity features such as Wi-Fi, Bluetooth, and GPS. Further, thewireless device 700 may include any number of additional components,such as analog to digital converters, digital to analog converters,graphics processing units, solid state drives, etc. Moreover, thewireless device 700 can include any type of device that may communicateover one or more wireless networks and that may include a poweramplifier that can be configured to support different communicationnetworks by using, for example, a bypass switch to modify the power orvoltage supplied to the power amplifier. For example, the wirelessdevice 700 may be a cellular phone, including a smartphone or adumbphone, a tablet, a laptop, a video game device, a wearable device(e.g., augmented reality or virtual reality glasses), a smart appliance,etc.

Terminology

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” The term “coupled” is used to refer tothe connection between two elements, the term refers to two or moreelements that may be either directly connected, or connected by way ofone or more intermediate elements. Additionally, the words “herein,”“above,” “below,” and words of similar import, when used in thisapplication, shall refer to this application as a whole and not to anyparticular portions of this application. Where the context permits,words in the above Detailed Description using the singular or pluralnumber may also include the plural or singular number respectively. Theword “or” in reference to a list of two or more items, that word coversall of the following interpretations of the word: any of the items inthe list, all of the items in the list, and any combination of the itemsin the list.

The above detailed description of embodiments of the inventions are notintended to be exhaustive or to limit the inventions to the precise formdisclosed above. While specific embodiments of, and examples for, theinventions are described above for illustrative purposes, variousequivalent modifications are possible within the scope of theinventions, as those skilled in the relevant art will recognize. Forexample, while processes or blocks are presented in a given order,alternative embodiments may perform routines having steps, or employsystems having blocks, in a different order, and some processes orblocks may be deleted, moved, added, subdivided, combined, and/ormodified. Each of these processes or blocks may be implemented in avariety of different ways. Also, while processes or blocks are at timesshown as being performed in series, these processes or blocks mayinstead be performed in parallel, or may be performed at differenttimes.

The teachings of the inventions provided herein can be applied to othersystems, not necessarily the system described above. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

Conditional language used herein, such as, among others, “can,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements and/or states. Thus, suchconditional language is not generally intended to imply that features,elements and/or states are in any way required for one or moreembodiments or that one or more embodiments necessarily include logicfor deciding, with or without author input or prompting, whether thesefeatures, elements and/or states are included or are to be performed inany particular embodiment.

While certain embodiments of the inventions have been described, theseembodiments have been presented by way of example only, and are notintended to limit the scope of the disclosure. Indeed, the novel methodsand systems described herein may be embodied in a variety of otherforms; furthermore, various omissions, substitutions and changes in theform of the methods and systems described herein may be made withoutdeparting from the spirit of the disclosure. The accompanying claims andtheir equivalents are intended to cover such forms or modifications aswould fall within the scope and spirit of the disclosure.

What is claimed is:
 1. A power amplifier module comprising: a firstpower amplifier configured to process frequencies associated with afirst communication band; and a bypass switch in communication with thefirst power amplifier and configured to provide a supply voltage to thefirst power amplifier, the supply voltage selected from a plurality ofsupply voltages based at least in part on a selected communicationnetwork, at least one of the supply voltages from the plurality ofsupply voltages enabling the first power amplifier to processfrequencies associated with a second communication band.
 2. The poweramplifier module of claim 1 wherein the plurality of supply voltagesincludes a battery supply voltage and a buck-converter supply voltage.3. The power amplifier module of claim 1 wherein the bypass switchincludes a p-channel field effect transistor in communication with abattery supply voltage.
 4. The power amplifier module of claim 1 whereinthe bypass switch includes a p-channel field effect transistor and ann-channel field effect transistor in communication with a buck-convertersupply voltage.
 5. The power amplifier module of claim 1 furthercomprising a second power amplifier in communication with a batterysupply voltage without being in communication with the bypass switch. 6.The power amplifier module of claim 5 wherein the second power amplifieris configured to process frequencies associated with 2G communication ofa different frequency band than the frequencies processed by the firstpower amplifier.
 7. The power amplifier module of claim 1 wherein thefirst communication band is a 2G communication band and the secondcommunication band is a non-2G communication band.
 8. A front-end modulecomprising: a power amplifier module including a first power amplifierand a bypass switch in communication with the first power amplifier, thefirst power amplifier configured to process a frequency associated witha first communication band, and the bypass switch configured to providea supply voltage to the first power amplifier, the supply voltageselected from a plurality of supply voltages based at least in part on aselected communication network, at least one of the supply voltages fromthe plurality of supply voltages enabling the power amplifier to processa frequency associated with a second communication band; and a directcurrent-direct current converter in communication with the poweramplifier module and configured to provide at least one supply voltagefrom the plurality of supply voltages to the bypass switch.
 9. Thefront-end module of claim 8 wherein the direct current-direct currentconverter includes a buck converter.
 10. The front-end module of claim 8further comprising an inductor-capacitor circuit between the directcurrent-direct current converter and the bypass switch.
 11. Thefront-end module of claim 8 wherein the plurality of supply voltagesincludes a battery supply voltage and a buck-converter supply voltage.12. The front-end module of claim 8 wherein the bypass switch includes ap-channel field effect transistor in communication with a battery supplyvoltage.
 13. The front-end module of claim 8 wherein the bypass switchincludes a p-channel field effect transistor and an n-channel fieldeffect transistor in communication with a buck-converter supply voltage.14. The front-end module of claim 8 wherein the power amplifier modulefurther includes a second power amplifier in direct communication with abattery supply voltage.
 15. The front-end module of claim 14 wherein thesecond power amplifier is configured to process a different frequencyassociated with 2G communication than the frequency processed by thefirst power amplifier.
 16. A wireless device comprising: an antennaconfigured to transmit a signal from a front-end module; and thefront-end module including a power amplifier module and a directcurrent-direct current converter in communication with the poweramplifier module, the power amplifier module including a first poweramplifier and a bypass switch in communication with the first poweramplifier via a first communication path, the power amplifier configuredto process a frequency associated with a first communication network,and the bypass switch configured to provide a supply voltage to thefirst power amplifier, the supply voltage selected from a plurality ofsupply voltages based at least in part on a selected communicationnetwork from a plurality of communication networks, at least one of thesupply voltages from the plurality of supply voltages enabling the firstpower amplifier to process a frequency associated with a secondcommunication network, and the direct current-direct current converterconfigured to provide at least one supply voltage from the plurality ofsupply voltages to the bypass switch.
 17. The wireless device of claim16 wherein the bypass switch includes a single transistor incommunication with a battery supply voltage.
 18. The wireless device ofclaim 16 wherein the bypass switch includes a pair of transistors incommunication with a direct current-direct current converter supplyvoltage.
 19. The wireless device of claim 16 wherein a first transistorof the pair of transistors is a p-channel transistor and the secondtransistor of the pair of transistors is an n-channel transistor. 20.The wireless device of claim 16 wherein the power amplifier modulefurther includes a second power amplifier in communication with abattery supply voltage via a second communication path.
 21. The wirelessdevice of claim 20 wherein the second power amplifier is configured toprocess a different frequency associated with the first communicationnetwork than the frequency processed by the first power amplifier.